Methods for reducing nematode damage

ABSTRACT

A method of reducing damage to plant propagation material and plant organs which grow at a later time by a representative of the class Nematoda, which method comprises (i) treating the propagation material with (A) a chelating agent, and optionally (B) a macrocyclic lactone compound or another pesticide, before the material is sown or planted, or (ii) applying (A) a chelating agent, and optionally (B) a macrocyclic lactone compound or another pesticide, to the locus of the material or the treated material defined in (i) before its planting, and/or at its planting and/or during its growth.

The present invention relates to methods of improving the plant growth,methods of reducing soil-inhabiting pests, such as nematodes, attack onplant propagation material and plant organs which grow at a later time,and agrochemical combinations therefor.

The industry is continually seeking methods of improving the growth ofplant. Chemicals are typically used (i) to control undesirable species(for example, pests, such as insects, or vegetation, e.g., weeds, orfungi) and (ii) to promote plant growth (e.g., by providing nutrients),and thereby improve the growth of plants.

Soil-inhabiting pests such as nematodes damage crops by direct feedingdamage, by transmitting viruses and by facilitating bacterial and fungalinfections. The damage caused by nematodes to crops is often unspecificand easily confused with drought, malnutrition or disease. Typicalsymptoms are wilting, yellowing of the foliage and uneven or stuntedgrowth.

Methods to control nematodes and thereby protect the plant include (1)use of nematicides (such as aldicarb), including the use of seedtreatment nematicide (e.g. abamectin), and fumigants (e.g., methylbromide), (2) use of soil steaming, (3) use of crop rotation practices,which is effective against nematodes that are specific to a particularcrop; however, nematodes that have different hosts cannot be controlledby this method, and (4) use of nematode resistant or tolerant crops,which have been developed by conventional breeding or recombinant DNAtechnology (genetically modified plants).

It has now been found that a compound capable of forming a chelateunexpectedly provides a reduction in the damage caused by nematodes toplant propagation material and plant organs which grow at a later time.Further, it can been seen that an improvement in the control ofsoil-inhabiting pests by pesticides is achieved with the use of achelating agent.

Accordingly, in a first aspect, the present invention provides a methodof reducing damage to plant propagation material and plant organs whichgrow at a later time by a representative of the class Nematoda, whichmethod comprises (i) treating the propagation material with (A) achelating agent, and optionally (B) a macrocyclic lactone compound oranother pesticide, before the material is sown or planted, or (ii)applying (A) a chelating agent, and optionally (B) a macrocyclic lactonecompound or another pesticide, to the locus of the material or thetreated material defined in (i) before its planting, and/or at itsplanting and/or during its growth.

In the event (A) and (B) are used in (i) and (ii) defined in the firstaspect, the treatment or application of (A) and (B) can be eithersimultaneously or in succession.

It has also been found that a soil treated with variable amounts of apesticide, especially a macrocyclic lactone compound, and a chelatingagent result in an unexpected improvement in plant growth and control ofpests, particularly soil-inhabiting pests, such as nematodes. Thebenefit of the invention, therefore, can be attained (i) by treating thesoil with a composition comprising the combination (macrocyclic lactonecompound and a chelating agent) or (ii) by treating the soil eithersimultaneously or in succession with a macrocyclic lactone compound andchelating agent. Typically, the treatment of the soil with thecombination, whether as a single composition or as individualcomponents, can occur several occasions during the growth of a plant upto the harvest (i.e. before its planting, and/or at its planting and/orduring its growth). Indeed, the treatment of a single composition andthen the individual components in succession is also envisaged duringthe growth of a plant.

Therefore, in a second aspect, the present invention provides a methodof improving the growth of a plant (for example to improve the yield ofa crop harvest), which comprises (i) and (ii) as defined in the firstaspect.

Further, it has been found that the chelating agent improves the controlof soil-inhabiting pests by pesticides (e.g. insecticides, acaricidesand nematicides), and accordingly the present invention also provides anagrochemical composition for applying to the locus of a crop plant ortreatment of plant propagation material comprising (A) a chelating agentand (B) one or more pesticides (such as an insecticide, nematicide,acaricide), with the proviso that the composition consisting of, asactive ingredients, abamectin and N-phosphonomethyl valine is excluded.Examples of suitable pesticides include the macrocyclic lactonecompounds (B). Such a composition can be useful for the treatment (i)and application (ii) as defined in the first aspect.

In a further aspect, the present invention provides a method ofprotecting a plant propagation material and plant organs which grow at alater time by from attack by a representative of the class Nematoda,which method comprises (i) treating the propagation material with (A) achelating agent, and (B) a nematicide, before the material is sown orplanted, or (ii) applying (A) a chelating agent, and (B) a nematicide,to the locus of the material or the treated material defined in (i)before its planting, and/or at its planting and/or during its growth.

In an embodiment of the present invention, the chelating agent isapplied by the method defined in (ii). Preferably the chelating agent isapplied before the propagation material is planted and also during itgrowth up to harvest. The chelating agent is advantageously applied tothe locus of the propagation material after its planting.

The invention is described in more detail below.

Soil-Inhabiting Pests

The invention is especially effective against soil-inhabiting pests,which can damage a crop in the early stages of plant development. Forexample, the compositions can be formulated to target representative ofthe class Insecta and representatives of the order Acarnia, examples ofwhich include:

from the order Lepidoptera, for example, Acleris spp., Aegeria spp.,Agrotis spp., Alabama argillaceae, Amylois spp., Autographa spp.,Busseola fusca, Cadra cautella, Chilo spp., Crocidolomia binotalis,Diatraea spp., Diparopsis castanea, Elasmopalpus spp., Heliothis spp.,Mamestra brassicae, Phthorimaea operculella, Plutella xylostella,Scirpophaga spp., Sesamia spp., Spodoptera spp. and Tortrix spp.;from the order Coleoptera, for example, Agriotes spp., Anthonomus spp.,Atomaria linearis, Chaetocnema tibialis, Conotrachelus spp.,Cosmopolites spp., Curculio spp., Dermestes spp., Diabrotica spp.,Dilopoderus spp., Epilachna spp., Eremnus spp., Heteronychus spp.,Lissorhoptrus spp., Melolontha spp., Orycaephilus spp., Otiorhynchusspp., Phlyctinus spp., Popillia spp., Psylliodes spp., Rhizopertha spp.,Scarabeidae, Sitotroga spp., Somaticus spp., Tanymecus spp., Tenebriospp., Tribolium spp., Trogoderma spp. and Zabrus spp.;from the order Orthoptera, for example, Gryllotalpa spp.;from the order Isoptera, for example, Reticulitermes spp.;from the order Psocoptera, for example, Liposcelis spp.;from the order Anoplura, for example, Haematopinus spp., Linognathusspp., Pediculus spp., Pemphigus spp. and Phylloxera spp.;from the order Homoptera, for example, Eriosoma larigerum;from the order Hymenoptera, for example, Acromyrmex, Atta spp., Cephusspp., Lasius spp., Monomorium pharaonis, Neodiprion spp., Solenopsisspp. and Vespa spp.;from the order Diptera, for example, Tipula spp.;crucifer flea beetles (Phyllotreta spp.), root maggots (Delia spp.),cabbage seedpod weevil (Ceutorhynchus spp.) and aphids.

An especially important aspect of the invention is the control of pestsof the class Nematoda using the compounds according to the invention.There are a variety of nematodes, Endoparasitic-, Semiendoparasitic- andEctoparasitic nematodes; such as root knot nematodes, cyst-formingnematodes and also stem and leaf nematodes. The present invention isespecially directed towards root knot nematodes.

Examples of nematode pests include the species Meloidogyne spp. (forexample, Meloidogyne incoginita and Meloidogyne javanica, Meloidogynehapla, Meloidogyne arenari), Heterodera spp. (for example, Heteroderaglycines, (without the s) Heterodera carotae, Heterodera schachtii,Heterodora avenae and Heterodora trifolii), Globodera spp. (for example,Globodera rostochiensis), Radopholus spp. (for example, Radopholussimiles), Rotylenchulus spp., Pratylenchus spp. (for example,Pratylenchus neglectans and Pratylenchus penetrans), Aphelenchoidesspp., Helicotylenchus spp., Hoplolaimus spp., Paratrichodorus spp.,Longidorus spp., Nacobbus spp., Subanguina spp. Belonlaimus spp.,Criconemella spp., Criconemoides spp. Ditylenchus spp., Ditylenchusdipsaci, Dolichodorus spp., Hemicriconemoides spp., Hemicycliophoraspp., Hirschmaniella spp., Hypsoperine spp., Macroposthonia spp.,Melinius spp., Punctodera spp., Quinisulcius spp., Scutellonema spp.,Xiphinema spp., and Tylenchorhynchus spp.

The nematode species Meloidogyne spp., Heterodera spp., Rotylenchus spp.and Pratylenchus spp. are especially well controlled by the chelatingagents.

Chelating Agents

Chelating agents in the frame of the present invention are compoundscontaining at least two heteroatoms selected from O, N and S. Suchchelating agents are capable of entrapping (or sequestering) eitheranother compound or one or several metal atom cations. Preferredchelating agents are those capable of entrapping a metal cation.

The chelating agents which are used according to the present inventionare thus either in the metallated form (a metal cation is entrapped orsequestered by the chelating agent), or in the unmetallated form (nometal cation or another compound is sequestered, or another non-metalcompound is sequestered).

Examples of metal cations capable of being entrapped by the chelatingagent are preferably selected from cations of the first transition metalseries, especially Cr, Mn, Fe, Co, Ni, Cu and Zn, more especially Fe.

The chelating agents are also capable of forming acid addition salts,and those having at least one acidic group are capable of forming saltswith bases. Suitable salts with bases are, for example, metal salts,such as alkali metal or alkaline earth metal salts, for example, sodium,potassium or magnesium salts. The chelating agents may furthermoreentrap a metal cation and at the same time form a salt with one orseveral of the remaining acidic groups, as for example inFe³⁺Na¹⁺(EDTA⁴⁻), wherein EDTA is ethylenediaminotetraacetic acid, orZn²⁺Na₃ ¹⁺(DTPA⁵⁻), wherein DTPA is di-ethylenetriaminopentaacetic acid,or Na[FeEDDHA], wherein EDDHA isN,N′-ethylene-bis(hydroxyphenyl)glycine.

Chelating agents, therefore, generally comprise a plurality of groupsselected from carboxylic acid, hydroxyl, thiol, amino, phosphoric acid,or derivatives thereof, such as salt derivative.

Examples of preferred chelating agents include amino polycarboxylic acidchelating agents, aromatic and aliphatic carboxylic acid chelatingagents, amino acid chelating agents, ether polycarboxylic acid chelatingagents, phosphoric acid chelating agents, hydroxycarboxylic acidchelating agents and dimethylglyoxime. The chelating agents may be inthe form of the acid or salt.

Examples of aminopolycarboxylic chelating acids includeN,N′-ethylene-bis(hydroxyphenyl)glycines (EDDHA),ethylenediaminebis(2-hydroxy-methylphenylacetic acid) (EDDHMA),N,N′-ethylenebis(2-hydroxy-5-sulfophenyl)glycine (EDDHSA),ethylenediaminetetraacetic acid (EDTA),N-(2-hydroxyethyl)-ethylenediaminetetraacetic acid (HEDTA),cyclohexanediaminetetraacetic acid (CDTA), nitrilotriacetic acid (NTA),iminodiacetic acid (IDA), N-(2-hydroxyethyl)iminodiacetic acid (HIMDA),diethylenetriaminepentaacetic acid (DTPA), andglycoletherdiaminetetracetic acid (GEDTA) ethylenediaminedisuccinic acid(EDDS) and salts thereof.

Examples of the aromatic or aliphatic carboxylic acid chelating agentsto be used in the present invention include oxalic acid, succinic acid,pyruvic acid, salicylic acid and anthranilic acid, and salts, methylesters and ethyl esters thereof.

Further, examples of the amino acid chelating agents to be used in thepresent invention include glycine, serine, alanine, lysine, cystine,cysteine, ethionine, tyrosine and methionine, and salts and derivativesthereof.

Furthermore, examples of the ether polycarboxylic acid chelating agentsto be used in the present invention include compounds represented by thefollowing formula, compounds similar to the compounds represented by thefollowing formula and salts (e.g., sodium salt) thereof:

wherein Y₁ represents a hydrogen atom, a group represented by theformula —CH₂COOH or a group represented by the formula —COOH, and Z₁represents a hydrogen atom, a group represented by the formula —CH₂COOHor a group represented by the formula

Examples of the hydroxy carboxylic acid chelating agents to be used inthe present invention include malic acid, citric acid, glycolic acid,gluconic acid, heptonic acid, tartaric acid, lactic acid and saltsthereof.

Examples of the electrolyte chelating agents of polymer (includingoligomer) type to be used in the present invention include acrylic acidpolymers, maleic anhydride polymers, α-hydroxyacrylic acid polymers,itaconic acid polymers, copolymers comprising at least two of theconstituting monomers of these polymers and epoxysuccinic acid polymers.

In addition, chelating agents to be used in the present inventionfurther include ascorbic acid and thioglycollic acid, and salts thereof.

The most preferred chelating agents are amino polycarboxylic acids,aliphatic carboxylic acids and hydroxycarboxylic acids.

Especially suitable chelating agents are compounds of the formula (II)

whereinR₆ is —C₂-C₄-alkyl-X—C₁-C₆-alkyl, —C₂-C₄-alkyl-X—C₂-C₄—X—C₁-C₆-alkyl,—C₁-C₄-alkyl-COOH, —C₂-C₄-alkyl-N(R₁₀)R₁₁,—C₂-C₄-alkyl-X—C₂-C₄-alkyl-N(R₁₀)R₁₁,—C₂-C₄-alkyl-X—C₄-C₆-alkyl-X—C₂-C₄-alkyl-N(R₁₀)R₁₁, 2-hydroxyphenyl,2-hydroxybenzyl, —CH[phenyl-substituted]COOH, pyrid-2-yl,pyrimidin-2-yl, —CH₂-pyrid-2-yl, —CH₂-pyrimidin-2-yl or

Y is OH or SH; X is O, S or N(R₉);

R₇, R₈, R₉, R₁₀ and R₁₁ are independently of each other hydrogen,C₁-C₆-alkyl, —C₂-C₄-alkyl-X—C₁-C₆-alkyl,—C₂-C₄-alkyl-X—C₂-C₄—X—C₁-C₆-alkyl, —C₁-C₄-alkyl-COOH, 2-hydroxyphenyl,2-hydroxybenzyl, —CH[2-OH—C₆H₄]COOH, 2-pyridyl, 2-pyrimidinyl,—CH₂-pyrid-2-yl or —CH₂-pyrimidin-2-yl;or R₇ and R₈ together are ═CH—R₁₂;or R₁₀ and R₁₁ together are ═CH—R₁₂;R₁₂ is phenyl which is ortho-substituted with OR₁₃ or SR₁₃;phenyl-substituted is group of the formula

m is 1, 2 or 3; andR₁₃ is hydrogen or C₁-C₆-alkyl; and

Particularly preferred examples of chelating agents areN[—C₁-C₄-alkyl-COOH]₃ (NTA, nitrilotriacetic acid),[HOOC—CH₂—]₂NCH₂CH₂N[—CH₂—COOH]₂ (EDTA, ethylenediaminotetraaceticacid), HEDTA (N-(2-hydroxyethyl)-ethylenediaminetetraacetic acid),HOOC—CH₂—]₂NCH₂CH₂[HOOC—CH₂—]NCH₂CH₂N[—CH₂—COOH]₂ (DTPA,di-ethylenetriaminopentaacetic acid), and

wherein R₁ and R₂ are selected from the group consisting of hydrogen,halogen, C₁-C₆alkyl, Halogen-C₁-C₄alkyl, C₁-C₆Alkoxy,Halogen-C₁-C₆alkoxy and —SO₃H, and m and n are independently of eachother 1, 2 or 3, provided that each R₁ and R₂ can different if thereshould be more than one such substituent; especially preferred is acompound of the formula

a compound of the formula

a compound of the formula

or any mixture thereof; anda compound of the formula

a compound of the formula

In an embodiment, the chelating agent is metallated with a transitionmetal cation, preferably iron (III) or iron (II), especially iron (III).Examples of commercial iron chelates include Sequestrene™, (a ironchelate Na[FeEDDHA]), Farben™, Greental™, Basafer™, Libfer™, Torneo™,Ferreostrene™, Pantafer™, Septamin™. Bolikel™, Hampiron™, Ferrilene™,Rexene™, and Folcidin™. Commercial samples of metallated chelatingagents typically also contain a proportion of non-metallated chelatingagent.

Especially preferred are iron chelates of a EDDHA, such as (o,o-EDDHA),(o,p-EDDHA), (p,p-EDDHA), or a mixture thereof. The iron content of acomposition comprising an iron chelate is in general from 0.5 to 10,preferably from 1 to 8, in particular from 1.5 to 7, in particular from2 to 6 or of from 2 to 5.5, especially from 2.4 to 5.5, percent byweight, based on the weight of the composition.

A preferred mixture of an iron chelate of EDDHA is that comprising(o,o-EDDHA) and (o,p-EDDHA). Preferably, the molar ratio of the(o,p-EDDHA) to (o,o-EDDHA) is greater than 0.8:1, particularly between0.9:1 and 100:1. Especially, the ratio of o,p-EDDHA to o,o-EDDHA is from1:1 to 50:1, or from 2:1 to 10:1, or from 0.9:1 to 2:1.

A composition comprising the chelating agent may comprise additionalplant nutrients or plant fertilizers, these substances are preferablyselected from the group including calcium sulfate CaSO₄, calcium nitrateCa(NO₃)₂*4H₂O, calcium carbonate CaCO₃, potassium nitrate KNO₃,magnesium sulfate MgSO₄, potassium hydrogen phosphate KH₂PO₄, manganesesulfate MnSO₄, copper sulfate CuSO₄, zinc sulfate ZnSO₄, nickel chlorideNiCl₂, cobalt sulfate CoSO₄, potassium hydroxide KOH, sodium chlorideNaCl, boric acid H₃BO₃ and metal salts thereof, Na₂MoO₄. The preferredadditional nutrients may be present in an amount of 5% to 50% by weight,preferably of 10% to 25% by weight or of 15% to 20% by weight each.Preferred additional nutrients are urea, melamine, potassium oxide, andinorganic nitrates. The most preferred additional plant nutrient ispotassium oxide. Where the preferred additional nutrient is urea, whichmay be present in an amount of 1% to 20% by weight, preferably of 2% to10% by weight or of 3% to 7% by weight.

Use

Surprisingly, it has been found that the use of a chelating agent,especially in the metallated form, such as an agent chelating Fe²⁺ orFe³⁺, to the locus of the crop plants results in a quite unexpectedreduction in the nematode damage. The reduction in the damage providesenhanced plant growth characteristics, such as emergence, crop yield,protein content, more developed root system, tillering increase,increase in plant height, bigger leaf blade, less dead basal leaves,stronger tillers, greener leaf color, less fertilizers needed, lessseeds needed, less pesticides needed, more productive tillers, earlierflowering, early grain maturity, less plant verse (lodging), increasedshoot growth, improved plant vigor, and early germination.

The chelating agent is applied to the locus of the plant one or moreoccasions during the growth of the plant. It can be applied to theplanting site before the seed is sown, during the sowing of the seed,pre-emergence and/or post-emergence. The combination can also be usedwhile the plant is being grown in a green house and the use can becontinued after transplantation.

The use of the chelating agent can be via any suitable method, whichensures that the agent penetrates the soil, for example, nursery trayapplication, in furrow application, soil drenching, soil injection, dripirrigation, application through sprinklers or central pivot,incorporation into soil (broad cast or in band) are such methods.

The rate and frequency of use of the chelating agent on the plant mayvary within wide limits and depends on the type of use, the specificchelating agent, the nature of the soil, the method of application (pre-or post-emergence, etc.), the plant or pest to be controlled, theprevailing climatic conditions, and other factors governed by the methodof application, the time of application and the target plant.

Typical application rate of the chelating agent to the locus of the cropplant is from 45 to 10000 g per hectare (g/ha), especially from 90 to5000 g/ha, preferably from 140 to 2000 g/ha, most preferably from 230 to1000 g/ha. In the instance the chelating agent is a metallated chelate,such as iron EDDHA, application rate can be from 45 to 4800 g perhectare (g/ha), especially from 90 to 2400 g/ha, preferably from 140 to1500 g/ha, most preferably from 230 to 950 g/ha. The agent may beapplied once or several occasions during the growth of a plant dependingon the plant and circumstances, for example, 1 to 6 or 1 to 4 occasions(for a tomato crop harvest, for example, the combination can be appliedup to 4 times before harvest), and the amounts indicated above are foreach application.

The plant propagation material can also be treated with the chelatingagent before it is sown or planted, and then chelating agent can,optionally, be applied to the locus of the plant one or more occasionsduring the growth of the plant.

The term “plant propagation material” is understood to denote all thegenerative parts of the plant, such as seeds, which can be used for themultiplication of the latter and vegetative plant material such ascuttings and tubers (for example, potatoes). There may be mentioned,e.g., the seeds (in the strict sense), roots, fruits, tubers, bulbs,rhizomes, parts of plants. Germinated plants and young plants, which areto be transplanted after germination or after emergence from the soil,may also be mentioned. These young plants may be protected beforetransplantation by a total or partial treatment by immersion.

Further, the present invention is also applicable for use with a plantpropagation material, e.g., plant seed, that has already undergone atreatment with a pesticide.

Even distribution of the chelating agent (and optionally one or moreother pesticides) and adherence thereof to the seeds is desired duringtreatment of the propagation material, for example, a seed. Thetreatment could vary from a thin film of the formulation containing thechelating agent on a plant propagation material, such as a seed, wherethe original size and/or shape are recognizable to a thick film (such asa coating or pelleting with many layers of different materials (such ascarriers, for example, clays; different formulations, such as of activeingredients; polymers; and colourants) where the original shape and/orsize of the seed is no longer recognisable.

Accordingly, in an embodiment the chelating agent is adhered to thepropagation material, such a seed.

In an embodiment, the chelating agent is present on the seed in a pelletform.

Although it is believed that the present method can be applied to a seedin any physiological state, it is preferred that the seed be in asufficiently durable state that it incurs no damage during the treatmentprocess. Typically, the seed would be a seed that had been harvestedfrom the field; removed from the plant; and separated from any cob,stalk, outer husk, and surrounding pulp or other non-seed plantmaterial. The seed would preferably also be biologically stable to theextent that the treatment would cause no biological damage to the seed.It is believed that the treatment can be applied to the seed at any timebetween harvest of the seed and sowing of the seed or during the sowingprocess (seed directed applications).

The seed treatment occurs to an unsown seed, and the term “unsown seed”is meant to include seed at any period between the harvest of the seedand the sowing of the seed in the ground for the purpose of germinationand growth of the plant.

Treatment to an unsown seed is not meant to include those practices inwhich the pesticide is applied to the soil but would include anyapplication practice that would target the seed during thesowing/planting process.

The treated plant propagation material of the present invention can betreated in the same manner as conventional plant propagation material.

The treated propagation material can be stored, handled, sowed andtilled in the same manner as any other pesticide treated material, suchas seeds.

Preferably, the treatment occurs before sowing of the seed so that theseed being sown/planted has been pre-treated.

Typical application rates of a chelating agent to a propagation materialalso vary depending on the specific use. For a seed, the rates can befrom 10 to 1000, preferably from 150 to 700, more preferably from 100 to600, especially from 150 to 400, grams of chelating agent per hectare ofseeds.

For a vegetable crop the chelating agent is typically applied in severaloccasions. For a fruit crop the chelating agent can also be applied inseveral occasions as in vegetables, however, a one shot application of achelating agent (e.g., SEQUESTRENE) is generally sufficient.

Target crop plants for use in the present invention include especiallyfield crops fruits, vegetables, nuts, berries, tropical plantations,ornamentals and others, such as wheat, barley, rye, oats, rice, maize,sorghum, beans, lentils, peas, soybeans, rape, mustard, poppy, sugar-and fodder-beet, cotton, flax, hemp, jute, sunflowers, castor oil,groundnuts, potatoes, tobacco, sugar cane, apples, pears, plums,peaches, nectarines, apricots, cherries, oranges, lemons, grapefruit,mandarins, olives vines, hops, almonds, walnuts, hazelnuts, avocado,bananas, tea, coffee, coconut, cocoa, natural rubber plants, oil plants,strawberries, raspberries, blackberries, spinach, lettuce, asparagus,cabbages, chinese kale, carrots, onions, tomatoes, cucumbers, pepper,eggplants, melons, paprika, chilli, roses, chrysanthemums andcarnations.

The plants can also be genetically modified.

The present invention has been found to be especially effective in highpH (such as 7 to 8.5) soil types.

Normally, a grower in the management of his crop would use one or moreother agronomic chemicals in combination with the chelating agent forthe treatment (i) and application (ii) as defined in the first aspect.Examples of agronomic chemicals include pesticides, plant nutrients orplant fertilizers.

Suitable examples of plant nutrients or plant fertilizers are calciumsulfate CaSO₄, calcium nitrate Ca(NO₃)₂*4H₂O, calcium carbonate CaCO₃,potassium nitrate KNO₃, magnesium sulfate MgSO₄, potassium hydrogenphosphate KH₂PO₄, manganese sulfate MnSO₄, copper sulfate CuSO₄, zincsulfate ZnSO₄, nickel chloride NiCl₂, cobalt sulfate CoSO₄, potassiumhydroxide KOH, sodium chloride NaCl, boric acid H₃BO₃ and metal saltsthereof, Na₂MoO₄. The nutrients may be present in an amount of 5% to 50%by weight, preferably of 10% to 25% by weight or of 15% to 20% by weighteach. Preferred additional nutrients are urea, melamine, potassiumoxide, and inorganic nitrates. The most preferred additional plantnutrient is potassium oxide. Where the preferred additional nutrient isurea, it is present in an amount of generally 1% to 20% by weight,preferably 2% to 10% by weight or of 3% to 7% by weight.

A single pesticide may have activity in more than area of pest control,for example, a pesticide may have fungicide, insecticide and nematicideactivity. Specifically, aldicarb is known for insecticide, acaricide andnematicide activity, while metam is known for insecticide, herbicide,fungicide and nematicide activity.

Accordingly, the action of the chelating agent can be significantlyimproved and adapted to the given circumstances by the use of one ormore pesticide compounds, such as a nematicide, insecticide and/orfungicide, used in agriculture, either as a seed treatment orapplication to the locus where the plant is grown.

Examples of pesticides include macrocyclic lactone compounds, which arecompounds having a ring in its chemical structure made up of twelve ormore atoms. The atoms may be selected from carbon, oxygen, nitrogen orsulfur, preferably the atoms are carbon and oxygen. In an embodiment,the ring has up to 20 atoms.

Examples of (B) include spinosad (737), avermectin and avermectinmonosaccharide derivatives, such as abamectin (1), doramectin(25-cyclohexyl-5-O-demethyl-25-de(1-methylpropyl)avermectin A_(1a); CASRN 117704-25-3), emamectin (291), eprinomectin((4″R)-4″-(acetylamino)-4″-deoxyavermectin B₁; CAS RN 123997-26-2),ivermectin (5-O-demethylayermectin A_(1a) (i) mixture with5-O-demethyl-25-de(1-methylpropyl)-25-(1-methylethyl)avermectin A_(1a)(ii), CAS RN 70288-86-7 (70161-11-4+70209-81-3)) and selamectin((5Z,25S)-25-cyclohexyl-4′-O-de(2,6-dideoxy-3-O-methyl-α-L-arabino-hexopyranosyl)-5-demethoxy-25-de(1-methylpropyl)-22,23-dihydro-5-(hydroxyimino)avermectinA_(1a); CAS RN 165108-07-6), and milbemycin derivatives, such asmilbemectin (557), milbemycin oxime((6R,25R)-5-demethoxy-28-deoxy-6,28-epoxy-25-ethyl-5-(hydroxyimino)milbemycinB mixture with(6R,25R)-5-demethoxy-28-deoxy-6,28-epoxy-5-(hydroxyimino)-25-methylmilbemycinB), moxidectin((6R,23E,25S)-5-O-demethyl-28-deoxy-25-[(1E)-1,3-dimethyl-1-butenyl]-6,28-epoxy-23-(methoxyimino)milbemycinB; CAS RN 113507-06-5), and SI0009 (a milbemycin B mixture of5-O-demethyl-28-deoxy-6,28-epoxy-25-methyl-13-[[(methoxyimino)phenylacetyl]oxy]-(6R,13R,25R)-(9Cl)and5-O-demethyl-28-deoxy-6,28-epoxy-25-ethyl-13-[[(methoxyimino)phenylacetyl]oxy]-(6R,13R,25R)-(9Cl);CAS RN 171249-10-8 and 171249-05-1).

The natural Avermectins, which can be obtained from Streptomycesavermitilis, are referred to as A1a, A1b, A2a, A2b, B1a, B1b, B2a andB2b. The compounds referred to as “A” and “B” have a methoxy radical andan OH group, respectively, in the 5-position. The “a” series and the “b”series are compounds in which the substituent R₁ (in position 25) is asec-butyl radical and an isopropyl radical, respectively. The number 1in the name of the compounds means that carbon atoms 22 and 23 arelinked by double bonds; the number 2 means that they are linked by asingle bond and that the C atom 23 carries an OH group.

In a preferred embodiment, the macrocyclic lactone lactone compound isan avermectin derivative, an avermectin monosaccharide derivative or amilbemycin derivative. Especially preferred are (i) avermectin B1derivatives (such as B1a, B1b, and other substitutents on the25-position); (ii) avermectin B derivatives having a single bond betweencarbon atoms 22 and 2; and the corresponding monosaccharide derivativesof (i) and (ii). Advantageously, abamectin is preferred as themacrocyclic lactone compound according to the present invention.

Derivatives of avermectin and avermectin monosaccharides can be obtainedby chemical syntheses, and include those disclosed in WO02/068442,WO02/068441, WO03/020738, WO03/053988 and WO03/095468.

Examples of nematicides are abamectin, carbamate nematicides (e.g.aldicarb, carbofuran, carbosulfan, oxamyl, aldoxycarb, ethoprop benomyl,alanycarb), organophosphorus nematicides (e.g. phenamiphos, fenamiphos,fensulfothion, terbufos, fosthiazate, phosphocarb, dichlofenthion,isamidofos, fosthietan, isazofos, ethoprophos, cadusafos, chlorpyrifos,heterophos, isamidofos, mecarphon, phorate, thionazin, triazophos,diamidafos, phosphamidon), methyl bromide, methyl iodide, carbondisulfide, 1,3-dichloropropene, chloropicrin, cytokinins, dazomet, DCIP,ethylene dibromide, GY-81, metam, methyl isocyanate, myrotheciumverrucaria composition, flupyrazofos, benchlothiaz,[2-cyanoimino-3-ethylimidazolidin-1-yl]phosphonothioic acid O-ethylS-propyl ester, and bacillus firmus.

Abamectin, aldicarb, oxamyl, fenamiphos, ethoprophos, cadusafos,fosthiazate, 1,3-dichloropropene, chloropicrin and methyl bromide,methyl iodide are preferred nematicides for use in combination with thechelating agent.

Further, the chelating agent may also be used in combination with one ormore pesticides to improve the pest control.

Suitable examples of pesticides that can be used include acephate (2),acetamiprid (4), acetoprole(1-[5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-(methylsulfinyl)-1H-pyrazol-3-yl]ethanone),aldicarb (16), alpha-cypermethrin (202), azinphos-methyl (45),azoxystrobin (47), benalaxyl (56), benalaxyl-M (methylN-(2,6-dimethylphenyl)-N-(phenylacetyl)-D-alaninate), benclothiaz(7-chloro-1,2-benzisothiazole), bendicoarb (58), benfuracarb (60),benomyl (62), bensultap (66), bifenthrin (76), bitertanol (84),boscalid, (88) captan (114), carbendazim (116), carbaryl (115),carbofuran (118), carbosulfan (119), carboxin (120), carbpropamid(2,2-dichloro-N-[1-(4-chlorophenyl)ethyl]-1-ethyl-3-methylcyclopropanecarboxamide),chlorothalonil (142), chlorpyrifos (145), chlorpyrifos-methyl (146),clothianidin (165), copper salts (such as copper sulfate (172), cuprousoxide (181), Bordeaux mixture (87), copper hydroxide (169), coppersulfate (tribasic) (173), copper oxychloride (171) and copper octanoate(170)), cymoxanil (200), cypermethrin (201), cyproconazole (207),cyprodinil (208), cyromazine (209), dazomet (216), deltamethrin (223),diazinon (227), difenoconazole (247), dimethoate (262), dimoxystrobin(266), diniconazole (267), dinotefuran (271), Emamectin (291),endosulfan (294), ethaboxam(N-(cyano-2-thienylmethyl)-4-ethyl-2-(ethylamino)-5-thiazolecarboxamide),ethirimol (5-butyl-2-(ethylamino)-6-methyl-4(1H)-pyrimidinone),ethiprole (310), ethoprophos (312), famoxadone (322), fenamidone (325),fenamiphos (326), fenhexamid (334), fenpiclonil (341), fipronil (354),flonicamid (358), fluoxastrobin (382), fluazinam (363), fludioxonil(368), fluquinconazole (385), flutolanil (396), flutriafol (397),fonophos (O-ethyl S-phenyl ethylphosphonodithioate), fosetyl-aluminium(407), fuberidazole (409), furathiocarb (412), gamma-cyhalothrin (197),gamma-HCH (430), guazatine (422), heptenophos (432), hexaconazole (435),hymexazol (447), imazalil (449), imidacloprid (458), ipconazole (468),iprodione (470), isofenphos, lambda-cyhalothrin (198), mancozeb (496),maneb (497), metalaxyl (516), metalaxyl-M (517), metconazole (525),methiocarb (530), methyl-bromide (537), methyl-iodide (542),myclobutanil (564), nuarimol (587), omethoate (594), oxamyl (602),oxadixyl (601), oxine-copper (605), oxolinic acid (606), pencycuron(620), pefurazoate (618), phosmet (638), picoxystrobin (647), pirimicarb(651), prochloraz (659), procymidone (660), propamocarb (668),propiconazole (675), prothioconazole (685), pymetrozine (688),pyraclostrobin (690), pyrimethanil (705), pyroquilon (710), quintozene(716), silthiofam (729), spinosad (737), tebuconazole (761), tefluthrin(769), tetraconazole (778), thiabendazole (790), thiacloprid (791),thiamethoxam (792), thiodicarb (799), thiophanate-methyl (802), thiram(804), tolylfluanid(1,1-dichloro-N-[(dimethylamino)sulfonyl]-1-fluoro-N-(4-methylphenyl)methanesulfenamide),triadimenol (815), triazamate (818), triazophos (820), triazoxide (821),triticonazole (842), trifloxystrobin (832),3-Iodo-N*2*-(2-methanesulfonyl-1,1-dimethyl-ethyl)-N*1*-[2-methyl-4-(1,2,2,2-tetrafluoro-1-trifluoromethyl-ethyl)-phenyl]-phthalamide(code NNI-0001), and a compound of2-Pyridin-2-yl-2H-pyrazole-3-carboxylic acid(2-methylcarbamoyl-phenyl)-amide (code DKI-0001), such as2-(3-Chloro-pyridin-2-yl)-5-trifluoromethyl-2H-pyrazole-3-carboxylicacid (4-chloro-2-isopropylcarbamoyl-6-methyl-phenyl)-amide,2-(3-Chloro-pyridin-2-yl)-5-trifluoromethyl-2H-pyrazole-3-carboxylicacid (4-chloro-2-methyl-6-methylcarbamoyl-phenyl)-amide,5-Bromo-2-(3-chloro-pyridin-2-yl)-2H-pyrazole-3-carboxylic acid(4-chloro-2-isopropylcarbamoyl-6-methyl-phenyl)-amide,5-Bromo-2-(3-chloro-pyridin-2-yl)-2H-pyrazole-3-carboxylic acid(4-chloro-2-methyl-6-methylcarbamoyl-phenyl)amide, and3-Difluoromethyl-1-methyl-1 Hpyrazole-4-carboxylic acid(2-bicyclopropyl-2-yl-phenyl)-amide.

The pesticide, such as nematicide, insecticide and fungicide, could beused in the present invention via the treatment (i) or the application(ii) as defined in the first aspect. Therefore, in an instance, a seedcan be treated with abamectin and optionally one or more otherpesticides, and then the chelating agent is applied to the locus of theabamectin treated seed before its planting, at its planting and/orduring its growth. Further, the pesticides can also be applied to thelocus of the plant ropagation material (including a pesticide treatedplant propagation material) before it is planted, at its planting and/orduring its growth.

The methods of applying the pesticide to the locus of the propagationmaterial is via any suitable method, which ensures that the pesticidepenetrates the soil, for example, nursery tray application, in furrowapplication, soil drenching, soil injection, drip irrigation,application through sprinklers or central pivot, incorporation into soil(broad cast or in band) are such methods.

In the event the components are applied individually, the time elapsebetween applications of the components to the locus of the plant shouldbe such that on application of the second component the improved plantgrowth characteristics are demonstrated. The order of the application ofthe components is not critical, although preferred is the chelatingagent followed by the pesticide (e.g. nematicide, macrocyclic lactonecompound). The second component is applied within preferably 14, such as10, for example, 5, more preferably 4, especially 3, advantageously 1,days of the first component.

The rate and frequency of use of the pesticide on the plant may varywithin wide limits and depends on the specific pesticide, type of use,the nature of the soil, the method of application (pre- orpost-emergence, etc.), the plant or pest to be controlled, theprevailing climatic conditions, and other factors governed by the methodof application, the time of application and the target plant.

Typical application rate of abamectin to the locus of the crop plant isfrom 3 to 90 g per hectare (g/ha), especially from 6 to 60 g/ha,preferably from 9 to 40 g/ha, most preferably from 18 to 36 g/ha.

The pesticide may be applied once or several occasions in combinationwith the chelating agent (i.e. either simultaneously or in succession)during the growth of a plant depending on the plant and circumstances,for example, 1 to 6 or 1 to 4 occasions (for a tomato crop harvest, forexample, the combination can be applied up to 4 times before harvest),and the amounts indicated above for abamectin application rates are foreach application.

Typical application rates of a pesticide to a propagation material alsovary depending on the specific use, specific seed and specificpesticide, and a skilled person can determine the appropriate ratedepending on the specific circumstances so that the advantageous effectsof the present invention are exhibited.

A description of the structure of the pesticides mentioned herein can befound in the e-Pesticide Manual, version 3.1, 13th Edition, Ed. CDCTomlin, British Crop Protection Council, 2004-05.

The pesticide would protect the plant (including the plant propagationmaterial) against known pests. It would control, i.e. to inhibit ordestroy, pests occurring on plants, especially on useful plants (i.e.,plants having a value, e.g., a monetary value to the grower, such ascrops) and ornamentals in agriculture, in horticulture and in forestry,or on parts of such plants, such as the fruits, blossoms, leaves, stems,tubers or roots, while in some cases plant parts that grow later arestill protected against those pests.

The combination of abamectin and a chelating agent has been found to beparticularly effective in controlling nematodes, such as root-knotnematodes. An especially preferred combination is that comprising ironchelates of a EDDHA, and optionally other metals may also be present,such as sodium and potassium, as part of the chelating agent component.The action of the macrocyclic lactone compound together with a chelatingagent goes far beyond their action individually, and the chelating agentis providing an enhancement of the activity of the pesticide. Asynergistic effect exists whenever the action of, for example, theactive ingredient combination of the compounds is greater than the sumof the actions of the active ingredients applied separately. This can becalculated, for example, by the Colby formula, as described in COLBY, S.R., “Calculating synergistic and antagonistic response of herbicidecombinations”, Weeds 15, pages 20-22, 1967.

In the treatment (i) or application (ii) as defined in the first aspect,the chelating agent is generally in the form of a formulation containingother customary formulation adjuvant because it allows, for example,less burdensome handleability and application

A variety of formulation types exist: dry flowables (DF), liquidflowables (LF), true liquids (TL), emulsifiable concentrates (EC),suspension concentrates (SC), dusts (D), wettable powders (WP),suspoemulsions (SE), water-dispersible granules (WG) and others, such asencapsulations in polymeric substances. Some are registered for use onlyby commercial applicators using closed application systems, others arereadily available for on-farm use as dusts, slurries, water-solublebags, or liquid ready-to-apply formulations. Normally, however,commercial products are usually formulated as concentrates, where theend user will normally employ dilute formulations.

How the chelating agent is to be used will also determine theformulation type, for example, if the chelating agent is to be used as aseed treatment, then an aqueous composition is preferred.

The chelating agent and other agronomic chemicals (especiallypesticides) can be part of a single composition and used simultaneously(i.e. they are mixed together—often referred to as “a pre-mix”), or canbe separate products and used separately (e.g. sequentially). In theevent they are separate products, they can be mixed together shortlybefore treatment (i) or application (ii) by the user.

It is often more practical, where possible, for commercially availableformulations of the chelating agent and agronomic chemicals to bebrought together in the desired mixing ratio in a container (oftenreferred to as a “tank mixture”) in water shortly before application.

The present invention, therefore, also relates to an agrochemicalcomposition (e.g. “tank mixture” and “pre-mix”) for applying to thelocus of a crop plant or treatment of plant propagation materialcomprising (A) a chelating agent and (B) one or more pesticides (such asan insecticide, nematicide, acaricide), with the proviso that thecomposition consisting of, as active ingredients, abamectin andN-phosphonomethyl valine is excluded.

In an embodiment, the chelating agent and one or more agronomicchemicals (especially pesticides, such as nematicides (e.g. abamectin))are used in single composition that has been specifically formulated,the composition may be in the form one of the formulation typesmentioned above, the type of formulation being chosen in accordance withthe intended objectives and the prevailing circumstances; the chelatingagent and agronomic chemical are used together with at least one of theadjuvants customary in formulation technology, such as extenders, e.g.,solvents or solid carriers, or surface-active compounds (surfactants).

Suitable formulation adjuvants are, for example, solid carriers,solvents, stabilisers, slow-release adjuvants, dyes and optionallysurface-active substances (surfactants). Suitable carriers and adjuvantsin this case include all substances customarily used in crop protectionproducts, especially in products for controlling snails and slugs.Suitable adjuvants, such as solvents, solid carriers, surface-activecompounds, non-ionic surfactants, cationic surfactants, anionicsurfactants and further adjuvants in the compositions used in accordancewith the invention are, for example, the same as those described inEP-A-736252; are fully incorporated by reference herein for theirdisclosure relating to useful formulation adjuvants.

The compositions as a rule comprise 0.1 to 99%, in particular 0.1 to95%, of the combination and 1 to 99.9%, in particular 5 to 99.9%, of atleast one solid or liquid auxiliary, it being possible as a rule for 0to 25%, in particular 0.1 to 20%, of the composition to be surfactants(% is in each case percent by weight). While concentrated compositionsare more preferred as commercial goods, the end user as a rule usesdilute compositions that comprise considerably lower concentrations ofthe combination. Preferred compositions are composed, in particular, asfollows (%=percent by weight):

Emulsifiable Concentrates:

-   combination: 1 to 90%, preferably 5 to 20%-   surfactant: 1 to 30%, preferably 10 to 20%-   solvent: balance

Dusts:

-   combination: 0.1 to 10%, preferably 0.1 to 1%-   solid carrier: 99.9 to 90%, preferably 99.9 to 99%

Suspension Concentrates:

-   combination: 5 to 60%, preferably 10 to 40%-   surfactant: 1 to 40%, preferably 2 to 30%-   water: balance

Wettable Powders:

-   combination: 0.5 to 90%, preferably 1 to 80%-   surfactant: 0.5 to 20%, preferably 1 to 15%-   solid carrier: balance

Granules:

-   combination: 0.5 to 60%, preferably 3 to 40%-   solid carrier: 99.5 to 70%, preferably 97 to 85%

Examples of specific formulation examples for use in crop protection aregiven below (%=percent by weight):

EXAMPLE F1 Emulsifiable Concentrates

a) b) c) combination 25% 40% 40% Calcium dodecylbenzenesulphonate  5% 8%  6% Castor oil polyethylene glycol ether (36 mol of EO)  5% — —Tributylphenol polyethylene glycol ether — 12%  4% (30 mol of EO)N-methyl pyrrolidone 25% 35% 40% Xylene mixture 40%  5% 10%

Mixing of finely ground macrocyclic lactone compound, chelating agentand additives gives an emulsion concentrate, which by dilution withwater, affords emulsions of the desired concentration.

EXAMPLE F2 Solutions

a) b) c) combination 40% 10% 5% Ethylene glycol monomethyl ether 10% 20%— Polyethylene glycol (MW 400) 15% 70% — N-methylpyrrolid-2-one 35% — —Epoxidized coconut oil — — 1% Aliphatic hydrocarbon (boiling range:160-190°) — — 94% 

Mixing of finely ground macrocyclic lactone compound, chelating agentand additives gives a solution suitable for use in the form ofmicrodrops.

EXAMPLE F3 Granules

a) b) c) d) combination 5% 10%  8% 21% Kaolin 94%  — 79% 54% Finelydivided silicic acid 1% — 13%  7% Attapulgite — 90% — 18%

The macrocyclic lactone compound and chelating agent are dissolved indichloromethane, the solution is sprayed onto the mixture of carriersand the solvent is evaporated under reduced pressure.

EXAMPLE F4 Wettable Powder

a) b) c) combination 25%  50% 75% Sodium lignosulphonate 5%  5% — Sodiumlauryl sulphate 3% —  5% Sodium diisobutylnaphthalene sulphonate —  6%10% Octylphenol polyethylene glycol ether —  2% — (7-8 mol of EO) Finelydivided silicic acid 5% 10% 10% Kaolin 62%  27% —

Macrocyclic lactone compound, chelating agent and additives are mixedand the mixture is ground in a suitable mill. This gives wettablepowders which can be diluted with water to give suspensions of thedesired concentration.

EXAMPLE F5 Extruder Granules

combination 60% Sodium lignosulphonate 10% Carboxymethylcellulose  1%Kaolin 29%

Macrocyclic lactone compound, chelating agent and additives are mixed,the mixture is ground, moistened with water, extruded and granulated,and the granules are dried in a stream of air.

EXAMPLE F6 Coated Granules

combination 3% Polyethylene glycol (MW 200) 3% Kaolin 94% 

In a mixer, the finely ground macrocyclic lactone compound and chelatingagent are applied uniformly to the kaolin which has been moistened withpolyethylene glycol. This gives dust-free coated granules.

EXAMPLE F7 Suspension Concentrate

combination 40% Ethylene glycol 10% Nonylphenol polyethylene glycolether (15 mol of EO)  6% Sodium lignosulphonate 10%Carboxymethylcellulose  1% Aqueous formaldehyde solution (37%) 0.2% Aqueous silicone oil emulsion (75%) 0.8%  Water 32%

Mixing of finely ground macrocyclic lactone compound, chelating agentand additives gives a suspension concentrate which, by dilution withwater, affords suspensions of the desired concentration.

The composition may also comprise further solid or liquid adjuvants,such as stabilisers, e.g., vegetable oils or epoxidised vegetable oils(e.g., epoxidised coconut oil, rapeseed oil or soybean oil), antifoams,e.g., silicone oil, preservatives, viscosity regulators, binders and/ortackifiers as well as fertilisers or other active ingredients forobtaining special effects, e.g., acaricides, bactericides, fungicides,nematicides, molluscicides or selective herbicides.

The following Examples are given by way of illustration and not by wayof limitation of the invention.

BIOLOGICAL EXAMPLES %=Percent by Weight Unless Otherwise IndicatedExperiment 1

Tomato plants are transplanted into a field infested with nematodes(Pratylenchus spp.) and treated with the treatments indicated in Table Ibelow 1, 14, 27 and 40 days after transplantation. The products areapplied by drenching 100 ml spray solution per plant. Plot size is 24 m²with 4 replicates. At harvest (up to 19 weeks later), all tomatoes arecollected and weighted. The check is an untreated control.

TABLE I Total average % yield weight increase % damage of tomatoes perover Treatments of roots treatment in kg check Check 40.8 701 — EDTA 500g ai/ha 25.8 784 12 EDTA 1000 g ai/ha 22.5 817 17

Experiment 2

Tomato plants are transplanted into a field infested with nematodes(Pratylenchus spp.) and treated with the treatments indicated in TableII below 1, 14, 27 and 40 days after transplantation. The products areapplied by drenching 100 ml spray solution per plant. Plot size is 24 m²with 4 replicates. At harvest (up to 19 weeks later), all tomatoes arecollected and weighted. The check is an untreated control.

TABLE II Total average % % damage weight of tomatoes yield increaseTreatments of roots per plant in gr over check Check 30.8 3143 — EDDHA500 g ai/ha 18.5 3500 11 EDDHA 1000 g ai/ha 13.8 3695 18

Experiment 3

Tomato plants are transplanted into a field infested with nematodes(Meloidogyne spp.) and treated with the treatments indicated in TableIII below 1, 18, 32 and 46 days after transplantation. The products areapplied by drenching 100 ml spray solution per plant. Plot size is 36.7m² with 4 replicates. At harvest (up to 19 weeks later), all tomatoesare collected and weighted. The check is an untreated control.

TABLE III Total average weight % % root of tomatoes per 100 yieldincrease Treatments galling plant in kgr over check Check 83.9 226 —EDDHA 500 g ai/ha 35 255 13 EDDHA 1000 g ai/ha 26.1 265 17

Experiment 4

Tomato plants are transplanted into a field infested with nematodes(Meloidogyne spp.) and treated with the treatments indicated in Table IVbelow 1, 18, 32 and 46 days after transplantation. The products areapplied by drenching 100 ml spray solution per plant. Plot size is 42.7m² with 4 replicates. At harvest (up to 19 weeks later), all tomatoesare collected and weighted. The check is an untreated control.

TABLE IV Total average weight % yield % average of tomatoes per 100increase over Treatments root galling plants in kg check Check 79.8 328— EDTA 500 g ai/ha 34.4 349 6 EDTA 1000 g ai/ha 23.7 360 10

Experiment 5

110 grams of dry sandy soil is put into plastic cups. The soil istreated by adding 25 ml of water containing given concentrations (inppm) of chemicals to the soil. The soil and water is carefully mixed andthereafter 1 ml of water containing 12,000 eggs of Meloidogyne is added.After 15 days of incubation, the samples are analyzed for live 2nd stagenematodes by sieving the sand and rinsing with tap water. The amount ofrinseate is adjusted to 20 ml. From the 20 ml, 3 samples of 1 ml aretaken and nematodes counted, using a counting chamber.

Concentration of % reduction Expected applied solution in Number of live2nd of live according to Treatments ppm stage nematodes stages Colbyformula Check 1651 Vertimec 3 1080 34.6 Sequestrene 3 1648 0.2 EDDHA 31649 0.1 EDTA 3 1650 0.1 Vertimec + Sequestrene 3 + 3 690 58.2 34.7Vertimec + EDDHA 3 + 3 735 55.5 34.7 Vertimec + EDTA 3 + 3 745 54.9 34.6

Experiment 6

50 grams of dry clay soil is put into plastic cups. The soil is treatedby adding 50 ml of water containing given concentrations (in ppm) ofchemicals to the soil. The soil and water is carefully mixed, andthereafter 1 ml of water containing 10,000 eggs of Meloidogyne is added.After 15 days of incubation, the samples are analyzed for live 2nd stagenematodes by sieving the clay, and rinsing with tap water. The amount ofrinseate is adjusted to 20 ml. From the 20 ml, 3 samples of 1 ml aretaken and nematodes counted, using a counting chamber.

Concentration of % reduction Expected applied solution in Number of live2nd of live according to Treatments ppm stage nematodes stages Colbyformula Check 1201 Vertimec 3 593 50.6 Sequestrene 3 1167 2.8 EDDHA 31197 0.3 EDTA 3 1200 0.1 Vertimec + Sequestrene 3 + 3 270 77.5 52.0Vertimec + EDDHA 3 + 3 274 77.2 50.8 Vertimec + EDTA 3 + 3 273 77.3 50.7

1. A method of reducing damage to plant propagation material and plantorgans which grow at a later time by a representative of the classNematoda, which method comprises (i) treating the propagation materialwith (A) a chelating agent, (B) abamectin and (C) azoxystrobin, beforethe material is sown or planted, or (ii) applying (A) a chelating agent,(B) abamectin and (C) azoxystrobin, to the locus of the material or thetreated material defined in (i) before its planting, and/or at itsplanting and/or during its growth.
 2. The method according to claim 1wherein the plant propagation material is selected from the cropsvegetables, citrus, soybeans, cotton, corn, potato, sugar beets, sugarcane, and cereals.
 3. The method according to claim 1 wherein the plantpropagation material is a seed.
 4. The method according to claim 1wherein chelating agent is a compound having at least two carboxylicgroups.
 5. The method according to claim 1 wherein the chelating agentis selected from an aminopolycarboxylic acid, aliphatic carboxylic acidand hydroxycarboxylic acid.
 6. The method according to claim 1 whereinthe chelating agent is metallated.
 7. The method according to claim 6wherein the metallated chelating agent is an iron chelate.
 8. The methodaccording to claim 1 wherein one or more pesticides are present incombination with chelating agent in the treatment (i) or in theapplication (ii).
 9. The method according to claim 8 wherein thepesticide is a nematicide.
 10. The method according to claim 8 whereinthe pesticide is abamectin, carbamate nematicides selected fromaldicarb, carbofuran, carbosulfan, oxamyl, aldoxycarb, ethoprop benomyl,and alanycarb; organophosphorus nematicides selected from phenamiphos,fenamiphos, fensulfothion, terbufos, fosthiazate, phosphocarb,dichlofenthion, isamidofos, fosthietan, isazofos, ethoprophos,cadusafos, chlorpyrifos, heterophos, isamidofos, mecarphon, phorate,thionazin, triazophos, diamidafos, and phosphamidon; methyl bromide,methyl iodide, carbon disulfide, 1,3-dichloropropene, chloropicrin,cytokinins, dazomet, DCIP, ethylene dibromide, GY-81, metam, methylisocyanate, myrothecium verrucaria composition, flupyrazofos,benchlothiaz, [2-cyanoimino-3-ethylimidazolidin-1-yl]phosphonothioicacid O-ethyl S-propyl ester, and bacillus firmus.
 11. A method ofimproving the growth of a plant, which comprises (i) and (ii) as definedin claim
 1. 12. A method of improving the control of soil-inhabitingpests towards a plant by a pesticide, which comprises (i) treating thepropagation material with (A) a chelating agent, (B) abamectin and (C)azoxystrobin, before the material is sown or planted, or (ii) applying(A) a chelating agent, (B) abamectin and (C) azoxystrobin, to the locusof the material or the treated material defined in (i) before itsplanting, and/or at its planting and/or during its growth. 13.(canceled)
 14. (canceled)
 15. (canceled)
 16. A method of protecting aplant propagation material and plant organs which grow at a later timeby from attack by a representative of the class Nematoda, which methodcomprises (i) treating the propagation material with (A) a chelatingagent, (B) abamectin and (C) azoxystrobin, before the material is sownor planted, or (ii) applying (A) a chelating agent, (B) abamectin and(C) azoxystrobin, to the locus of the material or the treated materialdefined in (i) before its planting, and/or at its planting and/or duringits growth.
 17. (canceled)